Revert "drm/msm/dpu: drop dpu_encoder_phys_ops.atomic_mode_set"

Revert "drm/msm/dpu: drop dpu_encoder_phys_ops.atomic_mode_set"

In the DPU driver blank IRQ handling is called from a vblank worker and
can happen outside of the irq_enable / irq_disable pair. Using the
worker makes that completely asynchronous with the rest of the code.
Revert commit d13f638c9b88 ("drm/msm/dpu: drop
dpu_encoder_phys_ops.atomic_mode_set") to fix vblank IRQ assignment for
CMD DSI panels.

Call trace:
 dpu_encoder_phys_cmd_control_vblank_irq+0x218/0x294
  dpu_encoder_toggle_vblank_for_crtc+0x160/0x194
  dpu_crtc_vblank+0xbc/0x228
  dpu_kms_enable_vblank+0x18/0x24
  vblank_ctrl_worker+0x34/0x6c
  process_one_work+0x218/0x620
  worker_thread+0x1ac/0x37c
  kthread+0x114/0x118
  ret_from_fork+0x10/0x20

Fixes: d13f638c9b88 ("drm/msm/dpu: drop dpu_encoder_phys_ops.atomic_mode_set")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/595065/
Link: https://lore.kernel.org/r/20240522-dpu-revert-ams-v2-1-b37825d708e1@linaro.org
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Signed-off-by: Rob Clark <robdclark@chromium.org>